In an industrial plant, field devices, such as instruments or transmitters, are used to obtain process variables from industrial process and other devices or equipment than field device, such as Rotating Equipment. Many systems are configured to control or monitor these field devices to ensure proper functioning of the field devices. These systems are configured to communicate with the field devices through an input-output (IO) module. The IO module is configured to communicate with a plurality of field devices and systems in the plant.
Commissioning is a process for testing equipment, the IO module and the field devices connected to the IO module. Commissioning may include different works or activities to verify if equipment, the IO modules and the field devices function according to those design objectives or specifications. One of these works or activities is testing or validation. Testing works or activities could be further break down into smaller identifiable units of works or acts. These smaller identifiable units can be predetermined into two groups: IO module check and field device check, targeting at the IO module and the field device, respectively. Check functions of the IO module check and the field device check aim to automate execution of testing or validation of the IO modules and the field devices connected to the IO modules based on respective configurations of the IO modules and the field devices. Types of the check functions are as follows.
IO Module Input and Output Check
IO module is configured by downloading its design specification. This check is a test to verify specification for each channel which is the information downloaded to each channel.
The function of IO Module Input and Output Check is also to measure the precision of input and output of the IO module. Precision of input and out of IO module is measured by tolerance level. Tolerance level is a difference between data written to and read from the IO module. The smaller the tolerance level, more precise is the input and out of the IO module. When the IO module is configured dual-redundant, each side of the IOM is checked respectively.
The following are types of the IO module Input Output check:
IOM Input Check-refers to a check function that tests the precision of Input (analog or digital) of the IOM
IOM Output Check-refers to a check function that tests the precision of output (analog or digital) of the IOM
Device Input and Output Check
The Device Input and Output Check is to confirm that the field device operates correctly and is within the acceptable range in precision by giving actual signals or simulated input and output signals.
In an operating plant, field devices measure actual process variables (for example, temperature), or respond to actual commands received from an operator or control system. During commissioning stage, a plan is not in operation. Thus, there is no physical environment for field device to measure the process variables. For the purpose of checking and commissioning, field devices are set in a simulated environment and a simulated signal or command is given to the device.
There are two device loops, for example, a device input loop and a device output loop. The device input loop is a connection between an input device and the IOM and the device output loop is another connection between the IOM and output device.
The following are types of field device check:
Manual check-refers to a check function that allows a user to create instructions for tasks that cannot be automated by tools. Physical effort or action is required.
Connection check-refers to a check function that determines the connection and the physical locations of field devices in a plant.
HART input loop check-refers to a check function that evaluates if signals between “an input field device” and “an IO module” are correctly transmitted. In device input loop check, signals are sent to field devices through an IOM and the field device will generate a corresponding signals to the IOM. Deviation of the two signals is compared with a predefined threshold (tolerance level). If the deviation is within the threshold, then, the signal is correctly transmitted. If the deviation is greater than the threshold, the signal is incorrectly transmitted.
HART output loop check-refers to a check function that evaluates if the signals between “an output field device” and “an IO module” are correctly transmitted.
For testing of signals transmitted between the IO module and the field devices for each commissioning task, at least two persons, a field operator and a control room operator, have to be in close communication with each other during the commissioning process in a conventional method.
FIG. 1 illustrates a conventional method for field device Input Loop Check. A control room operator sends a simulated signal (e.g. a temperature value) to an input field device (e.g. a temperature sensor) through an IO module. The value is written to the field device and transmitted to an IO module. Another operator uses a calibrator to read the transmitted signal from the IO module. Difference between the two signals is computed. If the difference is within a predefined threshold, then signal is correctly transmitted.
FIG. 2 illustrates a conventional method for field device Output Loop Check. A control room operator sends a command to an output field device (e.g. a valve) through an IO module. The output field device responds to the command (e.g. valve position) and sends a corresponding signal to the IO module. Another operator uses a calibrator to read the transmitted signal from the IO module. Difference between the two signals is computed. If the difference is within a predefined threshold, then signal is correctly transmitted.
FIG. 3 shows how series of Input and Out Loop checks are executed. While multiple commissioning signals are sent to the IO module or the field devices, a method for executing a series of input and output Loop checks involves multiple users to coordinate and test the field devices one by one at a time in sequential order.
In a typical plant, there are hundreds or thousands of field devices, in which commissioning is a tedious process and requires a lot of manpower and time. There is a need for an improved method and system for performing input and output loop check for the field devices.
A recently developed smart configurable IO module (SCIO) is capable to support multiple channels and to toggle analog/digital input/output functions for each channel. By supporting multiple channels, multiple commissioning signals can be transmitted through the SCIO in parallel, instead of one by one. This function of the parallel transmission of multiple commissioning signals for the multiple channels allows fast execution of field device input and output loop checks.
A new system and method for fast and convenient execution of field device input and output loop checks is disclosed herein by using a smart configurable IO module.